JPH07327365A - Assembly set composed of static converter with control switch and its control circuit - Google Patents

Abstract

PURPOSE: To achieve a constant-output operation by constituting of an output filter consisting of at least one transformer and one capacitor, a double-voltage rectifier or an auxiliary circuit, depending on a load circuit. CONSTITUTION: A stationary converter self-oscillates under unloaded conditions, depends on a switch peak-peak voltage control, and operates unloaded without applying an overvoltage to a switch. Then, when an auxiliary circuit, consisting of C1, C2, C3, D2, D3, and D4, is connected to the secondary side of a transformer, an output capacity CS is charged up to a maximum voltage Voutm via a diode D. When an output current Iout approaches 0, a charge which is constantly outputted from the auxiliary circuit through the diode D4 exceeds the charge required for the output, so that the diode D is turned on, thus providing an assembler set which consists of a stationary converter that can achieve a constant-output operation by improving the output characteristics of the converter and its control circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flyback type static converter having a control switch in connection with a boost rectifier, and an assembly set including the control circuit thereof.

[0002]

BACKGROUND OF THE INVENTION The converter of the present invention is particularly advantageous when used as a power source for gas discharge lamps. FIG. 1 schematically shows a basic circuit of a known flyback monoswitch converter. Designers use soft switching as a switch (ie resonant switch)
If desired to obtain, a capacitor (C) and an anti-parallel diode (Dp) (this diode may be, for example, a source / drain diode such as a MOS transistor) are connected to the switch terminal as shown in FIG. . In these known circuits, the secondary circuit of the transformer is composed of only the diode D and the capacitor Cs for achieving a constant output operation.

[0003]

An object of the present invention is to realize a basic circuit of a static converter of this type (more specifically, it is realized by a switch control circuit, a secondary side rectifier circuit, and a transformer). Improved,
Achieving a constant output operation. Another object of the invention is to propose various improved circuits of DC / DC or DC / AC converters arranged around the same unit for powering a gas discharge lamp.

[0004]

According to the present invention, in an assembly set including a zero volt switching type resonant static converter including a mono switch on a primary side and a rectifying circuit on a secondary side, at least one transformer (T
r), an output filter composed of at least one capacitor (CS), and an auxiliary circuit existing in the voltage doubler rectifier or the load circuit.

[0005]

As described above, the assembly set including the static converter having such a control switch and the control circuit thereof can achieve a constant output operation.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. The first improvement that this invention brings to the static converter for this invention is the realization of a transformer with negligible leakage inductance. This is accomplished by printing the wound coil directly on the printed circuit board provided with the converter and inserting the magnetic core around this. When a transformer is so achieved, the effect of leakage inductance will be negligible in converter operation. Then, at that time, the equivalent circuit model of the transformer shown in FIG. 3 can be used. Thus, for different operating modes using such an improved transformer for the converter shown in FIG. 2, the following effective results are obtained.

I-Standard operation in the completely demagnetized state t ₀ to t ₁ : The switch K is closed. Primary current "I
p ″ increases linearly. The diode (D) is off. At −t = t ₁ , (K) is the current “Ipma.
x "is switched off. t ₁ to t ₂ : This is a resonance process between Vin, Lm, and C. At -t = t ₂ , Vs = -Vout.
(Output voltage). Turn on diode D. From t ₂ to t ₃ : Vk = Vin + (n1 / n2), Vou
t and Ip = 0, the current Im decreases linearly, and -t = t
_{At 3} , ID = 0 and the diode (D) is turned on. From t ₃ to t ₄ : Im = Ip, a resonance state is set. -T =
At t ₄ , Ve = 0 and Vk = Vin. t ₄ to t ₅ : Resonant state. At −t = t ₅ , (n1
> N2) .Vout> Vin, the diode (D) is turned on. From t ₅ t _6: circuit for controlling the switch detects the decreasing slope of the voltage Vk, closing the switch between t ₅ and t _6. With such a control loop, the converter self-oscillates.

This waveform and its corresponding state diagram are shown in FIG.
Is shown in. When the switch (K) is opened, the switch terminal voltage becomes Vin + t (n1 / n2) · Vout. This is an image of the output voltage Vout when Vin moves. Therefore, controlling the peak voltage of the switch is equivalent to controlling the output voltage.

II Operation in incomplete degaussing state (see FIG. 5). In order to increase the output power, it is necessary to increase the current "Ipmax" cut off by the switch. If the switch control circuit defines a fixed maximum degauss period, there is a value of Fpmax at which D does not return to 0 due to the current flowing through the diode (D). Therefore, demagnetization of the magnetic core becomes incomplete. And closing the switch becomes difficult (time t ₀ ),
Opening the switch (time t ₁ ) maintains resonance. Switching losses will be higher but will remain acceptable. This is because the overpower operation is transient and limited to a short time. The operation of the converter from complete demagnetization to incomplete demagnetization is continuous. Since the period "t ₂ -t _1" is a short almost constant, even operating conditions would any one, with the control circuit, the period "t ₃ from opening time t ₁ of the switch
It is easy to fix −t ₁ ″. Conduction period “t
_1- t ₀ is related to the input voltage “Vin” and the output power. Here again, controlling the peak voltage of the switch is equivalent to controlling the output voltage of the converter.

III Operation under No-Load Condition Under no-load condition, the circuit does not behave like a flyback converter. The current iD is equal to 0 and there is a resonance between the capacitance (C) and the magnetic inductance (Lm) (FIG. 6). The decreasing slope of the switch voltage is used to drive the switch closure. The converter is self-oscillating and relies on switch peak voltage control. The converter operates with no load without overvoltage on the switch. By controlling the switch peak voltage when the converter is unloaded, a high output voltage can be achieved without disturbing other operating modes. Transformer 2
On the next side, (C1), (C2), (C
3), (D1), (D2), (D3), (D4) only needs to be added. If such an auxiliary circuit is connected, the output capacitance (CS) will be the maximum voltage Voutm.
Is charged up. Voutm is determined by the following. -Input voltage "Vin",-Controlled switch peak voltage suitable for switch "Vkpeuk",-Turn ratio of transformer m = n2 / n1, and Voutm = m (Vkpeak-Vin),

As long as the converter is the current source, the value of the current cannot overshoot. When the output impedance tends to infinity, the output current tends to zero and the auxiliary circuit can operate. The charge Q flowing through the capacitor (C1) in any period
Has a relationship of Q = C1 · ΔVC1. Where ΔVC1
Is the voltage rise of the capacitor C1. The electric charge supplied to the output when the output current is 0 is stored in the capacitor CS,
Voltage rises above the value Voutm. Then, the diode D turns on. In order to know the maximum value of Vout that can be achieved by the auxiliary circuit, Vout> Vout
Consider the equilibrium state of m. The capacitors C1, C2 and C3 are charged to an almost constant voltage. The ripple voltage, that is, the peak-to-peak value ΔVS of the voltage ΔS, occurs at node A, but is simply a value greater than or equal to 0 (because of the diode D1). The capacitance C2 is equal to ΔVS by the diode D2. Is charged up to. The peak-to-peak ripple voltage in the node A is generated in the node B, which is a voltage to which VC2 is added.
The diode D4 charges the capacitor CS to the peak voltage of the node B, that is, 2 · ΔVS. No load, ΔVS = m · V
Since it is kpeak, the no-load output voltage is 2 · m · Vkp
Ascend to eak. Voltage-VS, voltage VAM, voltage V
The BM is shown in FIG.

The output characteristics of the converter of FIG. 7 are shown in FIG. It consists of two parts. Zone 1 is
Zone 2 corresponds to the contribution of the auxiliary circuit, corresponding to the characteristics of the converter without the boost auxiliary circuit. In short, capacity CS
Is charged to the voltage Voutm through the diode D. And, when the output current Iout goes to 0, the charge supplied from the auxiliary circuit through the diode D4 always exceeds the charge required for the output. Diode D
Turns on. The voltage Vout is 2 · m · Vkpea
increase to k. The auxiliary circuit elements are all m · Vkp
It is determined by the maximum voltage of eak. With the classical topology, very little operation could be achieved with only a fairly high voltage rating of the power device.

A similar purpose is achieved by the device shown in FIGS. 10 (a) and 10 (b). In normal operation, the charge provided to the output from C4 through diode D6 is not sufficient to be stored in C5.
When the output impedance tends to be infinite, the voltage of the capacitor CS is VCSm = m (Vkpeak-Vin)
The charge brought to the output at all times by C4 can charge C5, since The diode D maintains the voltage Vcsm of m (Vkpeak-Vin), and the capacitor C5 is charged to the voltage ΔVS. The output voltage Vout is Vout = m (Vkpeak-Vin)
+ ΔVS or 2 · mVkpeak-m · Vin. In that device, diode D7, connected in parallel with diodes D5 and D6, is not essential, but it helps to increase efficiency as one voltage drop can be eliminated.

Therefore, using the auxiliary circuit provided on the secondary side of the converter as shown in FIGS. 7 and 10 (a) and (b) improves the output characteristics of the converter. In this way, both the output characteristics and the operation of the converter are improved, which is a very special transformer realization (providing a negligible leakage inertia to the coser) and a secondary side of the converter. The auxiliary circuit, that is, a boost rectifier type circuit. The combination described above is new. Because it is very unlikely to know that means, which are obviously completely independent of each other, work together for a common purpose. As will be described later, the function of the static converter is that the above two means, namely, a special transformer winding and a step-up rectifier circuit provided on the secondary side of the converter are used when the converter is used as a power source for gas discharge lamps in particular. Is further improved if it is combined with a third alternative means, a switch (K) where control is forced.

Another object of the invention is an assembly set including a single switch static converter and its control circuitry. The circuit diagram shown in FIG. 11 is an example of a control circuit realized by the present invention. The switch drive signals for the circuits shown in FIGS. 7 (a) and 10 (b) are accomplished by the functions described below using the following circuits. 1. Switch peak voltage control. There is a peak voltage priority limiting loop and the purpose of this circuit is to prevent the peak voltage of the switch from overshooting from a constant value regardless of operating conditions. 2. Synchronized with decreasing slope of switch voltage. Switch voltage V
When a decreasing slope of k is detected, the switch (K) turns on in synchronization with the phenomenon. Its function is, in fact, important under normal operating conditions (full degaussing) and no-load operation.

3. Control (prohibition) circuit. To prevent the detection of the decreasing slope of the voltage Vk from being impossible due to floating high frequency ripple, the synchronization circuit is disabled for a predetermined period after the switch is opened. 4. Achieving a certain switch opening period. In incomplete demagnetization, the closing drive of the switch occurs before the synchronization signal generated by the decreasing slope of the voltage Vk. It is achieved by a circuit which fixes the maximum duration of the opening of the switch (t ₃ -t _1). Above the selected value of the maximum current Ipmas interrupted by the switch, the open period of the switch is fixed. It is equal to the degaussing period, at which the degaussing is incomplete. 5. Adjustment of switch conduction time "Ton". Switch conduction time (t ₁ -t ₀₎ is the result of the adjustment loop (output voltage, output current, output power, etc.) is given by and the switch peak voltage control. 6. Limit of switch conduction time "Ton" to a predetermined maximum value. If the switch conduction time is limited, the output power is also limited. At that time, the input voltage is
Less than the minimum value to protect the converter.

7. Initialization circuit. To guarantee a soft start, the initialization circuit outputs the output of the regulation loop integrator,
Fixed to a voltage that produces a short switch conduction time. After that, the period gradually increases.

8. Adjustment loop. Designed to power a gas discharge lamp, the converter acts as a voltage source at no load (high-voltage control at start-up), then immediately after start-up as a current source, and finally in very few operating conditions. And acts as a power source with controlled output power under overload conditions.

To obtain this, the output signal is usually
Iout "is controlled. However, this solution makes it difficult to regulate the output voltage Vout under no-load conditions, because the transition between no-load operation and over-output operation is
This is because it can be done only by very fast instruction changes. On the other hand, in no-load operation the output voltage cannot be controlled without the voltage regulation loop. To avoid this drawback, a new type of adjustment has been achieved in the present invention. Here, the output current "I" related to the input current (Im)
The sum of the voltage "out" and the output voltage "Vout" related to the input voltage (Vin) is adjusted.

This principle is explained by the following simple mathematical reasoning. Now, assume that A and B are two variables, which are equal in the initial stage (A = B = A ₀ ), but after a certain time, their sum changes so as to be constant (A + B = Constant). . Then, A = A ₀ + X, and B = A ₀ −X. Can be written. The product of variables P is initially
It is equal to P ₀ = (P ₀ = A ₀ ² ). At that arbitrary time, P = A · B = A ₀ ² −X ² . _{Formula: (P-P 0) /} P 0 = ΔP / P 0 = -X 2 / A 0 2. If X is small, it can be seen that ΔP / P ₀ << ΔA / A ₀ .
For example, if A ₀ = 10 and X = 2, then ΔA
/ A ₀ = −ΔB / B ₀ = 20% and ΔP / P ₀ is 4%. If A is the image voltage of the output voltage, A = K · Vout. If B is the image voltage of the output current, then B = K ′ · Vout. Therefore, if both output current meanings and output voltage meanings are given equal importance, both of these “additional adjustments” under well-selected and only a few operating conditions are subject to error of a few percent. It enables the design of converter output adjusted by.

Furthermore, when the output current is 0 (no load operation), only the meaning of the output voltage is taken into consideration, and the converter
Operates under voltage regulation. Finally, under the over output operation condition, the output voltage is low, and it is not necessary to consider the meaning of the output voltage. The converter then operates under current regulation. The example of FIG. 11 shows that the regulation circuit is very simple and that all converter operating modes are controlled by only one variable, the control voltage Vo. Then, when the control voltage is the maximum, there are scale factors K and K ′ such that the output voltage is adjusted to the maximum value in the no-load operation and the output current is adjusted to the maximum value in the short-circuit operation. Therefore, the control voltage Vc makes it possible to successfully handle the change from the start of a load such as a gas discharge lamp to a stable and constant operating state. During this time, the regulation loop compensates for effects associated with the environment such as lamp aging or ambient temperature.

9. Current amplifier for fast drive of drive circuit and transistor switch. Among other things, the achievement of a transformer with negligible leakage inductance is "P
It is possible to use a "lanar" type transformer or a transformer whose winding is made by a scientific or mechanical stamp. To supply an alternating voltage to the load,
Normally, the DC / DC converter described above according to the invention is combined with a 4-switch full wave bridge circuit. Another object of the invention is to achieve some DC / AC converters which are achieved by the combination of the means already mentioned, namely the layout of the transformer windings, the boost rectification secondary circuit, the original control of the flyback type structure. It is to propose a new device.

An AC voltage similar to that shown in FIG. 12 can be produced with the DC / AC converter technique shown in FIG. 13 which combines two flyback type devices improved by the present invention. The operation according to the sequence shown in FIG. 12 is as follows. -While in state 1, switches K'and K1 are open. The converter composed of K, Tr, D and Cs is shown in FIG.
It operates according to the principles shown in 3, 4, and 5. Current flows through the load, through K2 (closed) and through (Rs) (resistor for measuring output current). this is,
The voltage is in the positive period. -While in state 2, switches K, K'and K1 are open. There is no transfer of energy from the input source Vin to the output. The capacitance CS is discharged to the load through RS and K2. -During State 3, the discharge of the capacity CS is finished. The diodes D, K1, the reverse diode, and K2 are conducting. Vab = 0. -While in state 4, switches K and K2 are open.
The converter consisting of K ', T'r, D', C's operates according to the principle shown in FIGS. Current flows through the load, through K1 (closed), and through (RS). For state 1, the output current is reversed at the load. This is the period when the voltage is negative. -State 5, switches K, K'and K2 are open and switch K1 is closed. C's discharges.
And so on….

The starter requires a high voltage to power the gas discharge lamp. In order to achieve the first sign reversal of the signal Vab, a boost rectifier circuit according to the principle of FIG. 7 must be incorporated in the converter device. FIG. 14 shows a device proposed as a power supply for a gas discharge lamp. Furthermore, powering some gas discharge lamps requires a special starting sequence. A voltage of 10 KV to 30 KV applied to a discharge lamp produces an electric arc. In the first microsecond, the voltage decreases to less than 2KV. After about 10 microseconds, it becomes 400 V or less. Finally, after about 100 milliseconds, it settles between 50 and 110V. And
The polarity of the discharge lamp, which periodically inverts at a frequency of 100 to 500 Hz, prevents premature wear of the discharge lamp. Such a power supply couples a starter element to a DC / AC converter.

In the circuit diagram of the converter for a gas discharge lamp shown in FIG. 15, a novel device in which a starter is combined in a DC / AC converter has been achieved. The switch is controlled with the purpose of producing a start-up sequence followed by a steady state as shown in FIG. In state 1, K1 is on and K and K2 are off. The converter consisting of K ', T'r, D', and C's operates like a no-load flyback if the lamp LD is off. Therefore, the voltage Vb is 150 to 2
Increase to 00V. 1 for the control circuit because of its value
8. Acknowledge that a startup sequence that is the target of the next sequence is required. In state 2, K ', K1, K
2 is off. A flyback type converter composed of K, Tr, D, and C'S in which a booster circuit achieved by the principle shown in FIG. 7 is formed is possible. The current flowing through the load is 0, and the voltages Va and Vb are 400
Increase to V. In state 3, K and K2 are off. A flyback type converter consisting of K ', T'r, D', C's is possible, closing switch K1 produces a voltage of 10 to 30 KV in the discharge lamp.
This is due to the transformer winding ratio of about 75 of the step-up transformer Tra. An electric arc occurs. The discharge lamp voltage drops sharply and then settles to 50 to 110V. The initial sequence ends. Then, state 4 of FIG.
Periodic reversal of the discharge lamp polarity is required, as shown in FIGS.

Control of the switches of the converter of FIG. 15 is accomplished by a control circuit as shown in FIG. The circuit of FIG. 17 and its functions are listed below. 1. Peak voltage control circuit for switches K and K '. 2. Synchronous circuit with the voltage decrease gradient of switches K and K '. 3. Forbidden circuit. This avoids detecting the decreasing slope of the voltage Vk caused by the whimsical high frequency ripple caused by the opening of the switch. 4. Circuit to achieve fixed switch open period 5. Switch conduction time (Ton) adjustment circuit. 6. A circuit that limits the switch conduction time (Ton) to a predetermined value. 7. In order to ensure soft start of the initialization circuit and converter, or when the polarity change [both (+) → (−) and (−) → (+)] of the voltage Vab starts, a short switch (K Or K ') it is necessary to initialize the integrator circuit of the regulation loop to a voltage which produces a conduction time. 8. The regulation loop, resistor Rs, is set in the converter of FIG. 15 to generate just a positive image load current, the sum of voltages Va and Vb being equal to the absolute value of voltage Vab. In this way, the need for that signal is resolved and a regulation loop similar to that already shown in FIG. 11 is achieved. 9. High-speed drive circuit for the switches K, K ', K1, K2 The circuits 1 to 9 described above are the same as the corresponding circuits shown in FIG. 10. Switches K1 and K depending on the polarity of the voltage Vab
2 selection circuit 11. 12. Oscillator with a period that determines the period during which the polarity of voltage changes. 13. Frequency (circuit) by two frequency dividers that guarantees that the period in which the polarity of the signal Vab changes is the same. Monitor circuit for on / off lamp operation. Voltage Vb
Is the end (one) of the polarity of the polarity voltage Vab,
If it is increased to V, the start-up sequence occurs as shown in FIG. 14. Reference voltage generation circuit. 15. A circuit that corrects the scale factor K according to the output voltage. In FIG. 11, the sum K · Vout + K ′ · Iou
It can be seen that by adjusting t, the converter output is also adjusted around the value of Vout with good accuracy. Here, K takes a certain value if Vab is lower than 85V, and takes another value if Vab is higher than 85V. As shown in 1, the accuracy of constant output adjustment is
It is achieved in a range twice as large as the output voltage Vab. 16. A circuit for matching the control voltage Vc to the lamp operating conditions. The purpose of its function is to achieve constant illumination as soon as the lamp starts, but the effect of the illumination varies considerably over the first few minutes of operation. As explained above,
The DC / AC converter for a gas discharge lamp shown in FIG. 15 is such that if the energy is stored in one transformer with only one flyback type device,
And if that energy is alternately stored through the secondary winding, which is originally coupled to the primary winding, by a novel device achieved with two switches and two rectifying diodes, then simplification To be done.

FIG. 18 shows the novel device described above, which operates in steady state according to the sequence shown in FIG. State 1: Switch (K) operates at high frequency. K
1 is turned off, and K2 is turned on. Energy is supplied to the power source Vin through the secondary windings (S1, S2) according to the principle shown in FIGS.
From the load to the filter capacitance Cs of energy. This voltage Vab is positive. -State 2: K and K1 are turned off, K2 is turned on. The capacity Cs is discharging to the load. The voltage Vab is decreasing. State 3: K2 is turned on and Cs is discharged. The diode D and the switch K1 reverse diode are conducting. The voltage Vab is zero. It is also possible to jump directly from state 2 to state 4 and set the lamp current again in the opposite direction at high speed. -State 4: Switch 4K operates at high frequency. K2 is turned off and K1 is turned on. Energy is transferred from the power supply Vin to the filter capacitor C's of energy through the secondary windings (S3, S4) according to the principles shown in FIGS. The voltage Vab is negative. State 5: K and K2 are turned off, K1 is turned on. The capacity Cs' is being discharged to the load. The voltage Vab is decreasing, etc ...

The magnetic core of the transformer shown in FIG.
It is made up of two pieces of outer shape "E" joined together. A void is provided in the central leg portion. To obtain the converter of FIG. 18 operating according to the sequence described above, the windings are laid out according to the novel means shown in FIG. 19 in order to reduce the leakage flux, and on the one hand the primary winding Between the wires (P1, P2) and the secondary windings (S1, S2), on the other hand, the primary windings (P1, P2)
It is necessary to obtain a symmetrical arrangement between 2) and the secondary windings (S3, S4). Primary winding (P1, P2)
Consists of two identical coils wound around side legs (1), (2) respectively. Then, a common current flows through the coils connected in series, and a combined magnetic flux is generated in the central leg and the air gap. Secondary winding (SI,
Each of S2) and (S3, S4) is also so wrapped around the side leg. The magnetic flux path f flowing through the central leg 3 and the side legs 1
Considering 1, the positive current flowing through the dot terminal P1 and the positive current flowing through the dot terminal 2S2 create an added ampere-turn. The magnetic flux path f flowing through the central leg 3 and the side legs 2
Considering 2, the positive current flowing through the dot terminal P1 and the positive current flowing through the dot terminal S3 create an added ampere-turn.

Most of the energy goes to the output
When the switch K2 is closed, the secondary winding (SI,
2 through S2) when switch K1 is closed
It flows through the next winding (S3, S4). That is, it flows during the operation period of the switch K. -If K turns on, energy storage in the central leg 3 takes place (Fig. 19). -If K is turned off, the magnetomotive force, which is a power supply that is immediately formed, will cause the same windings (SI, S2) and (S3, S4) placed in parallel and closed with different impedances. Power the same wound magnetic ends (1) and (2) (FIG. 19). K2 turns on, K
When 1 is turned off, (S3, S4) becomes a short circuit (low energy loss), and (SI, S2) stores most of the energy stored in the air gap in the load again through the filter capacitance Cs. Conversely, K1 turns on and K
When 2 is turned off, (SI, S2) becomes a short circuit and (S3, S4) stores most of the energy stored in the air gap in the load again through the filter capacitance C's.

In order to supply electric power to a lamp such as a gas discharge in the circuit of FIG. 18, the element already shown in FIG. 7 (or 10 and 10-2) or the boosting auxiliary circuit Ca is provided at the output. It is necessary to. FIG. 20 shows the principle of the assembly set. The starting sequence is the same as that shown in FIG. Switch KI
And when K2 is turned off, the booster circuit operates according to the principle described in FIG. The capacitance provided between the terminals S3 and S4 has a low impedance when compared with the impedance of the booster circuit between the terminals S1 and S2. Therefore, the voltage of the windings (S3, S4) is charged up to about 400V. A winding (S that is effective to supply power to a booster circuit that stores the starting pulse energy in CS (S
It is very low when compared with the voltage of I, S2).

FIG. 21 shows an example in which a control circuit for supplying power to the gas discharge lamp converter shown in FIG. 20 is realized. The primary structure of the converter is the same as that shown in FIG. The control circuit is shown in FIGS. 11 and 17 as 1, 2, 3, 4, although there are some variations to achieve.
Features numbered 5, 6, and 9 are used.
In the regulation loop (circuit number (8)), the input power is
The converter according to the invention is regulated because it produces a certain amount of constant energy loss, whatever the variation of the input and output voltage. For that loop, the sensing of the input voltage Vin and the input current sensed by the resistance (Rs) provided in the primary circuit of the converter is also used. The secondary circuit of the converter is the same as the structure shown in FIG. Thus, among the control circuits shown in FIG. 21 (although there are some variations to the achievement), 11,
The functions numbered 12, 13, 14, 15, and 16 are reissued.

The circuit numbered 17 has been added to adjust the voltage VB when the booster circuit is enabled. In the circuit numbered 15, the scale factor K is adjusted according to the input voltage Vin, which is above and below the selected value in the middle of the input voltage range. In this way, the accuracy of the power adjustment depends on the total input voltage V
It is appropriate in the range of in. Therefore,
The converter shown in FIG. 0 operates the same as the converter shown in FIG. 15 having the same structure. Since the secondary current flows through the diode (D or D ') and the switch (K2 or K1) as required, a switch inverting integral rectifier can be used instead of the diodes D and D'. The structure shown in FIG. 22, which is a structure of a novel DC / AC converter having three static switches, that is, a MOS transistor or an IGBT type, can be achieved. An inverting integral rectifier is used for the DC / AC converter. In order to facilitate the driving of the switch by using the same ground, the relative positions of the secondary winding and the switches K1 and K2 can be interchanged.

In order to supply power to the gas discharge lamp, the circuit of FIG. 22 uses the capacitance Ca, diode Da, and diode shown in FIG.
It must then be completed with a starting circuit consisting of the step-up primary winding of the transformer Tra. Capacity Ca
Cannot be directly charged to 400V by the boost circuit enabled by the main converter as in the circuit shown in FIG. One independent element is Ca
used to charge the s. In FIG. 23, the auxiliary charging circuit Ca is achieved by the voltage boosting rectifier circuit shown in FIG. Any other topology capable of charging the capacity Ca up to about 400V is also suitable. The capacitor C1, one of which is grounded between the diode Da and the primary winding of the transformer Tra, and the other of which is grounded, is a snubber network for the switch K1 which generates the starting pulse.

The converter shown in FIG. 23 operates according to the following sequence. -Lamp start sequence: switches K, K1 and K
2 turns off. By enabling the auxiliary charging circuit Ca, the capacitors Ca and Cs can be charged up to 400V. When the switch K1 is turned on for about 1 microsecond, the capacitance Ca discharges through the primary winding of the transformer Tra, the primary winding of which produces a very high voltage, Cs is the secondary winding of the main transformer. No discharge due to impedance in (S1, S2) -steady state: K1 turned off after start pulse,
K2 turns on and switch K is enabled for operation.
Then, the auxiliary charging circuit Ca stops. Switch K1
The inverting diode of is the primary winding of the transformer (P1, P
2) and as a rectifier for a flyback converter operating with secondary windings (S1, S2). The windings (S3, S4) are short-circuited by K2 and the filter capacitance C's. The capacitance of C'S, like the instantaneous voltage across it, has a small AC change during the operation of the switch. The average value of the voltage of the capacitor C ′S is 0
Is. The output voltage Vab is positive. The negative change of the voltage Vab is achieved symmetrically by closing K1 and opening K2, K (which is operating at high frequency). It will be in a steady state.

The MOS transistors are switches K and K1.
And is well suited to achieving K2. However, most of the commonly found components have source-drain diodes that have a significant reversal recovery time which reduces efficiency. The reversal recovery time of the inverting diode of the transistor can be significantly reduced by turning on the transistor when the inverting diode of the transistor behaves like a rectifier (synchronous rectification). For example, K2 is turned on while voltage Vab is positive, and K1, which is normally turned off, is turned on when its inverting diode is conducting. With today's state of the art, the feature offers higher efficiency and / or the possibility of high frequency operation.

FIG. 24 shows an example in which the converter control circuit for the gas discharge lamp shown in FIG. 23 is realized. The primary structure of the converter is the same as that shown in FIG. The converter control circuit again has the functions numbered 1, 2, 3, 4, 5, 6, 8 and 9 shown in FIG. 21 and the numbers equal to those of FIGS. 11 and 17. Use the attached function. The secondary structure of the converter behaves similarly to that shown in FIG. The control circuit shown in FIG. 24 uses the functions numbered 11, 12, 13, 14, 15 and 16 of FIG. 20, although there are some variations in implementation. Charging auxiliary circuit C
The oscillator circuit 11 has been modified to take into account the control of the switch Ka by a. In the steady state, the circuit will be switched when the polarity is reversed to prevent overcurrent from occurring in the primary circuit of the converter if the capacitance CS (or C'S) is not completely discharged. , Switch K is turned off. During start-up, the circuit has a capacitance Ca (and CS) of approximately 400V.
The charging auxiliary circuit Ca is allowed to operate until it is charged (starting condition).

The other functions shown in the circuit diagram of Figure 24 are necessary for the operation of the converter of Figure 23: When the switch K is prohibited,
Controls voltage polarity changes. 19. The circuit turns on switch K1 to generate the starting pulse. 20. The circuit interferes with the normal rectifying action of the inverting diode of switch K1 or K2 and turns on the corresponding switch. Unless the semiconductor manufacturer improves its characteristics, the switch (MOS transistor or IG
The ability of BT) to reduce the integrated diode inversion recovery time is ineffective. 21. The circuit includes a switch Ka (C for starting preparation).
energy to a) and then to switch K (steady state operation). 22. An under voltage lock circuit (UVLO) regulates the power supply (not shown) to the converter electronics. If the input voltage Vin is too low, the converter will not operate. Finally, when the starting pulse occurs, switch K1
A high current flows through. Special switch KO only for the starting circuit
It is economically more advantageous to use (MOS type transistors or IGBTs or thyristors) and, as shown in FIGS. 20 and 30, ordinary low-rated switches for K1 and K2. Thus, FIG.
The control circuit shown in Figures 24 and 24 is slightly modified; however, there is no change to the proposed invention for this type of converter. FIG. 25 shows a particular switch KO used in the starting circuit.

[0038]

With the above construction, it is possible to obtain an assembler set including a static converter and a control circuit for achieving a constant output operation.

[Brief description of drawings]

FIG. 1 shows the basic circuit of a known flyback monoswitch converter.

FIG. 2 shows a converter for powering a gas discharge lamp.

FIG. 3 shows an equivalent circuit of an improved transformer according to the present invention.

FIG. 4 shows a static converter normally operated in the fully demagnetized state.

FIG. 5 shows the waveform of a static converter operated in a completely degaussed state.

FIG. 6 shows waveforms for a static converter operated under no load conditions.

FIG. 7 DC / DC including a boost rectifier auxiliary circuit on the secondary side
A static converter is shown.

8 shows voltage waveforms at points A and B at the transformer secondary side terminal in the circuit diagram of FIG.

9 shows output characteristics of the converter shown in FIG.

10 (a) and (b) is a transformer 2;
A static converter with another auxiliary circuit is shown on the next side.

FIG. 11 shows a specific example of a control circuit realized by the present invention.

FIG. 12 shows an AC power supply voltage waveform to a load such as a gas discharge lamp.

FIG. 13 is a DC / A in which two flyback circuits are connected.
3 shows a C static converter.

FIG. 14 shows a DC / AC for powering a gas discharge lamp.

FIG. 15 shows a structure including a gas discharge lamp start circuit in a DC / AC converter.

FIG. 16 shows a control process of the converter.

17 shows a control circuit of the gas discharge lamp converter of FIG.

FIG. 18 shows a flyback converter that generates an AC voltage having the waveform of FIG.

FIG. 19 shows the external appearance of the magnetic core of the transformer used in FIG. 18 and its winding arrangement.

FIG. 20 shows a power supply circuit for a gas discharge lamp with a start circuit included in the converter.

21 shows an example of a control circuit of the converter shown in FIG.

FIG. 22 shows another DC / A without a rectifying diode on the secondary side.
The C converter is shown.

FIG. 23 shows the circuit of FIG. 22 applied to a gas discharge lamp.

FIG. 24 shows an example of an implementation of the converter control circuit of the gas discharge lamp of FIG.

FIG. 25 shows a modification of the converter of FIG. 23 using a special starter switch.

[Explanation of symbols]

 K, K ', K1, K2 switch LD lamp Dp, D, D', D7 diode S1, S2, S3 terminal P1, P2, S1, S2, S3, S4 winding Vin input voltage Vc control voltage Vkpeak switch peak voltage Iout Output current Ca Boosting auxiliary circuit C, C1, C2, C3, Cs Capacitance Rs Resistance Q Charge f1, f2 Magnetic flux path Lm Magnetic inductance

 ─────────────────────────────────────────────────── --Continued from the front page (31) Priority claim number 03-458-94-9 (32) Priority date November 17, 1994 (33) Priority claim country Switzerland (CH)

Claims (31)

[Claims] 1. An assembly set including a zero volt switching type resonant static converter including a mono switch on a primary side and a rectifying circuit on a secondary side, wherein at least one transformer (Tr) and at least one capacitor ( CS) and an auxiliary filter present in a voltage doubler rectifier or load circuit. 2. Assembly set according to claim 1, characterized in that the converter comprises two transformers and the output filter comprises two capacitors (CS, C5) connected in series. 3. One diode D, one diode D5, one diode D6, one capacitor C5, and one capacitor CS are all connected in series, and all these diodes have the same direction. And the capacitor C4 is connected in parallel with the set of diodes D and D5, and the common terminal of the diodes D and D5 is itself directly connected to the common terminal of the two capacitors CS and C5, The secondary winding includes a transformer Tr that is a closed circuit.
Assembly set described. 4. The assembly set of claim 3 including diodes D5 and D6 and a diode D7 connected in parallel in the same direction. 5. The secondary side includes a second voltage doubler rectifier circuit, and an output filter including a third capacitor connected in series with the capacitors (C5, CS). The converter according to claim 4. 6. A transformer (T having a diode D connected in series with an output capacitor CS, the secondary winding of which is a closed circuit).
r) and a diode (D
1) and a capacitor (C1) and one is a capacitor (C
1) and a diode (D1) and the other of which is connected in series with a voltage doubler rectifier circuit (D2, D3, D4, C3) connected to the cathode of the diode (D).
Converter according to claim 1, characterized in that it comprises a capacitor (C2) connected in parallel with a set of two diodes (D1 and D2) and in series with the diodes (D3, D4) of the voltage doubler rectifier circuit. . 7. An assembly set comprising a static converter having a control switch and its control circuit, said static converter having a control switch on the primary side and performing zero volt switching (Z, V, S). It is a flyback type converter, the transformer of the quiescent converter includes a leakage inductance that can be neglected by its achievement, and the sum of the voltages that mean the respective output currents Iout of the input current Iin and the input voltage V.
2. The assembly set according to claim 1, wherein the switch control circuit is controlled by a control voltage Vc to control the sum of the voltages, which means the respective output voltage Vout of in. 8. A control circuit of the switch (K), a peak voltage control circuit 1 of the switch K, a synchronization circuit 2 with a voltage decrease gradient of the switch K, and a circuit 4 for achieving a fixed switch turn-on period. A circuit 5 for adjusting the conduction time of the switch, and a conduction time limiting circuit 6 for the switch to which the sensing voltage of the output current Iout related to the control voltage Vc and the input current Iin and the output voltage Vout related to the input voltage Vin are supplied, 8. The assembly set according to claim 7, including a regulation loop, an initialization circuit 7, and an inhibition circuit 3. 9. The assembly set according to claim 1, wherein the control voltage Vc is constant during permanent steady state operation. 10. The assembly set according to claim 7, wherein the control voltage Vc is maximum in the load start-up sequence and then decreases to a minimum value. 11. The static converter includes a boost rectification auxiliary circuit on the secondary side thereof.
Assembly set described in 1 of 0. 12. The assembly set according to claim 11, wherein the static converter is a DC / DC type converter and includes only one transformer and a control switch provided in the primary circuit of the converter. 13. The static converter is a DC / AC type converter, and two transformers Tr, Tr 'each of which includes two switches K, K'controlled by the same control circuit on the primary side. Assembly set according to one of claims 7 to 11, characterized in that it comprises: 14. A diode and an output capacitor CS, C'S, each secondary circuit characterizing the output circuit.
Is a closed circuit, and the secondary circuit is an auxiliary switch K in which the secondary circuits of the transformers Tr and T'r are connected in parallel with the output capacitors CS and C'S.
1, K2 and these auxiliary switches K
14. The assembly set according to claim 13, wherein 1, K2 are controlled by the same control circuit. 15. The control circuit comprises two switches K, K '.
Drive circuit and switch K, depending on the sign of the voltage Vab
A circuit for selecting one or the other of K ', and a voltage V
Oscillator 1 having a cycle time that determines the bipolar period of ab 1
15. The assembly set according to claim 13 or 14, comprising: 16. Assembly set according to claim 15, characterized in that the control circuit again comprises the frequencies from the two dividing circuits 12. 17. At least one transformer Tra without additional switches, a primary winding of said transformer in series with a load, and one of the auxiliary switches K1.
17. The assembly set of claim 16, wherein the assembly set includes a starting circuit that includes a secondary winding of the transformer connected in series with one. 18. A circuit for monitoring the operation of a load and a scale factor, which can take two or several values depending on the output or input voltage, which enables a voltage range to be extended with the same precision by output regulation. 18. The assembly set of claim 17, including a generator circuit. 19. An external feedback loop for adjusting the control voltage Vc according to the load operation of the converter or ambient parameters.
Assembly set according to one of 8. 20. The assembly set of claim 19 including circuitry to generate a feedback loop reference voltage. 21. The winding of a transformer is provided directly on a printed circuit board carrying a converter, a magnetic core inserted around the winding, according to one of claims 7 to 20. Assembly set. 22. Assembly set according to one of claims 7 to 17, characterized in that the windings of the transformer are formed by chemical or mechanical stamping. 23. A converter, wherein the assembly set is arranged around a transformer winding of the converter comprising a magnetic core comprising at least three legs, the central leg of which is provided with an air gap (3). , Each of the primary windings (P1, P2) is wound around the side legs (1) and (2) so that the common current flowing through them creates a combined magnetic flux in the center leg and in the air gap Further marked by dots when considering the magnetic path (f1) flowing through the central leg (3) and the side leg (1), as made by two identical coils connected in series. The positive current flowing through the terminal (P1) and the positive current flowing through the terminal (S2) marked with a dot to create a combined ampere-turn, and of the central leg (3) and side Legs (2 It marked at point when considering magnetic path (f2) flowing through the terminal (P
1) so that the positive current flowing through and the positive current flowing through the terminal marked with a dot (S3) create a combined ampere-turn, the secondary coils (S1, S).
Assembly set according to claim 1 or 11, characterized in that each of 2) and (S3, S4) comprises a winding realized by being wound on a side leg. 24. The secondary winding (S1, S of each transformer)
2) and (S3, S4) form a closed circuit by a diode and an output capacitor (CS, C'S), and switch (K1, K2) network S1, S2-D-CS-K1 and S3, S4-. The output capacitor bypassed by D'-C'S-K2 has a common ground, and one of the loads is connected between the common terminal of the diode D and the capacitor CS and the other is the diode D '. 24. The assembly set according to claim 23, wherein the assembly set is connected between the capacitor and the capacitor C ′S. 25. The secondary windings S1-S2 of the transformer Tr
Each of S3-S4 is one of the switches K1 and K2,
Are connected in series by the assemblies S1-S2, K1; S3-S4, K2, which are closed circuits by the output capacitors CS, C5, and the assembly set comprises at least one transformer Tra coupled with an additional switch. The starting circuit, the secondary winding of the transformer Tra connected in series with the load, and the auxiliary switch K through the diode Da.
24. The assembly set of claim 23, including one of the transformers Tra and a primary winding of the transformer Tra connected in series. 26. A converter control circuit comprises a current amplifier 9 used as a drive circuit for switches K, K1 and K2, and a period Va of each polarity of voltage Vab having a period Va.
An oscillator (1 that determines the frequency by two drive circuits (12) that guarantees a signal that makes the polarity changes of b equal times.
1), an on / off lamp operation monitor circuit (13), a circuit (14) for generating a reference voltage, a circuit (15) for generating a scale factor K, and a circuit (16) for generating a control voltage.
26. The assembly set according to claim 25 or claim 25, comprising: 27. A control circuit for changing the polarity of the voltage during the inhibition period of the switch K, and the switch K.
26. An assembly set according to claim 24 or 25, characterized in that it comprises a circuit (19) enabling turn-on of 1 and a circuit for turning on the switch by turning on the inverting diodes of switches K1 and K2. . 28. The assembly set according to claim 1, wherein the auxiliary circuit is a voltage doubler rectifier circuit. 29. Assembly set according to one of claims 7 to 27, characterized in that the auxiliary circuit is a load circuit. 30. Each of the secondary windings of the transformer Tr includes an auxiliary switch K1, K2 and an output capacitor C.
In the assembly set, the secondary side of the transformer Tra has a load connected in series, and the primary side of the auxiliary switches K1 and K2 is connected by the starting capacitor Ca and the switch KO. Including a starting circuit consisting of at least one coupled transformer Tra which is a closed circuit at an intermediate terminal between
24. The assembly set according to claim 23, wherein: 31. A power supply for a gas discharge lamp, which uses the assembly set according to claim 1.